1. Technical Field
The present invention relates to optical imaging probes in general, and in particular to a handheld optical imaging probe.
2. Description of Related Art
A laser-based scanning fluorescence confocal imaging system typically includes a confocal configuration probe having a micromirror and an objective lens. Along with the confocal probe, the imaging system can obtain images of the subsurface of a sample based on the information within the light that returns from the sample after the sample has been irradiated with a low-coherence light source. An imaging depth in the order of a few hundred micrometers, with a spatial resolution of a few micrometers is relatively easy to achieve by using light intensity levels in the order of 100 μW. Thus, the above-mentioned imaging system is very useful for in vitro and in vivo tissue structure imaging applications.
Current endoscopes are typically more than 5 mm thick. The thickness of current endoscopes, especially when compared with their en face imaging area (about 2 mm wide) makes them undesirable as a needle endoscope for image-guided surgical procedures. One major challenge of making a thinner endoscope lies with the difficulty of designing a probe beam deflection system that is capable of covering a sufficient scan volume while constraining the probe diameter to be less than about 2 mm to minimize the invasiveness of the probe. A reasonable scan volume for providing sufficient image information would be a conical volume that is about 3 mm in length and about 2 mm in diameter at its maximum circumference.